Sixteen-year-old Alexander Dorf stood at the top of thestairs in his Tenafly, N.J., home two years ago, grinning broadly at hismother, Jami. He had just gotten a message on his Facebook wall that he’dbeen waiting for all his life.

From a Florida woman named Terri Barber, it read: “Hi,I was just wondering if your parents’ names are Jamie & Jeff?”Alexander recognized the name; he had searched the Internet for it himself withno luck. It belonged to the woman who had given birth to him.

Ms. Dorf and her husband, who had adopted Alexander as aninfant, were not surprised. Ms. Barber had reached out to them, too, a fewbeats after the e-mail to Alexander. “I sent Alex a message because Ifound him first, but I only asked him if you and Jeff were his parents,”Ms. Barber wrote. “I said nothing else. … Please let me know ifit’s O.K. if we speak…. Please don’t be upset.”

The Internet is changing nearly every chapter of adoption.It can now start with postings by couples looking for birth mothers who want toplace children, and end years later with birth mothers looking to reunite withchildren they’ve placed. A process that once relied on gatekeepers andofficial procedures can now be largely circumvented with a computer, Wi-Fi andsome luck.

“It used to be a slow process,” says AnyaLuchow, a psychologist who facilitates an adoption support group in BergenCounty, N.J., that includes the Dorfs. “And when the children wereminors, it was one that their adoptive parents could control.”

Now, says Leanne Jaffe, a Manhattan therapist (herself anadoptee) who specializes in adoption issues: “Kids, at the mostvulnerable time for developing identity, are plugged in online. Either they aresavvy enough to find their birth parents, or they spend time in places likeFacebook, where their birth parents can find them.”

There are stories of children as young as 13 approached bybirth parents online, and of children being contacted before they had been toldthey were adopted. Among the most cautionary of tales is that of Aimee L.Sword, who was convicted of having sex with her biological son, who was 14 atthe time, and whom she found on Facebook when yearly updates from his adoptivefamily stopped coming. “It’s uncharted territory,” Dr.Luchow says. What are the new rules? They are being made up as the participants— adoptees and their parents — go along.

When Linda Wachtel and her husband, Zev, adopted theirdaughter, Jessi, 19 years ago, things were different. Open adoption was stillrare. Birth mothers were kept at arm’s length.

They did have Jessi’s birth mother’s first name,Sharyn, but were not certain of her last; she knew them as Linda and Steve(Zev, they thought, was too easy to find). For awhile they used an 800 numberto communicate, set up, per the norm at the time, so that their whereaboutsremained secret. A few years in, they disconnected that line.

The Wachtels assumed Jessi would eventually want to meet herbirth mother but thought they would be in charge of the timing.

To that end, the Wachtels were open with their daughter, whohas two brothers who are not adopted, and who was always curious about hergenetic roots. As the Internet became a part of life, both Ms. Wachtel andJessi herself would do Google searches for Sharyn periodically, but come upempty. “Mostly I wanted to know what she looked like,” Jessi says.

One day, two years ago, Ms. Wachtel happened upon herson’s Facebook page, left open on a computer screen in their home. On awhim, she typed “Sharyn” and “Padula,” which was onepossible last name. Up popped a photo that “was eerily familiar,”Ms. Wachtel says. “It was like looking at my daughter.”

Ms. Padula answered within minutes. The two women talkedelectronically for much of the day. Then Ms. Wachtel left to pick up heryounger son from school and in those 20 minutes Jessi came home. Sitting at thefamily computer she noticed lindasteve92 on the screen, and by the time Ms.Wachtel got home, Jessi was in a conversation with Ms. Padula that had movedfrom e-mail through instant messaging, to the telephone, to video chat.

Ms. Padula had been looking for Jessi all along. She hadbeen 24 and the mother of three when she became pregnant in 1992, and she wasfighting with her then-boyfriend, now husband, who did not want another child. She regretted the adoption immediately, she says, and called the agency thenext day. She called the Wachtels’ 800 number periodically, too, until itwas disconnected.

Knowing that the family lived in New Jersey, that they hadnamed the baby Jessica, and that the adoptive father, whose name she thoughtwas Steve, was an anesthesiologist, she started by calling doctors with thatfirst name in that state. Years later she moved on to contacting every NewJersey Jessie, Jessy, Jessica and Jessyca on Facebook and MySpace, butapparently never tried Jessi. If she had, it might have been the teen who founda thunderbolt in her mailbox.

John, a professional guitarist in San Francisco, sat andstared at the MySpace page often over several weeks last year, trying to decidewhat to do. The young man’s face staring back from the screen looked justlike him. There were photos of him with a guitar, which tickled John, who hadjust learned he was the young man’s biological father. There was also oneof those surveys that kids forward around asking something like “50Things About Mike,” and included were the facts that he was adopted, bornin Palm Springs, and of Irish ancestry.

All John, who asked that his last name not be used, knewwhen he began his search was the date the boy was born, and the names of thebirth mother, the hospital and the adoption agency. Rummaging around online, hecame upon one of the many Web sites that seek to connect searching parties, andafter filling out a rudimentary form, he heard back via e-mail fromgsadoptionregistry.com.

The note contained contact information and a warning.“They told me, ‘This is a young guy, I suggest that you be veryrespectful of his adoptive parents because you don’t know how they aregoing to handle it,’ ” he recalls of the Web site, which will notconduct searches by or for adoptees younger than 18.

Mike was 21 by then, not a minor, but still, he had parents,and the question was whether to reach out to him directly or to go through hisfamily.

Many friends advised him to approach the young man directly,assuming that the adoptive parents would be hostile. “But I decided to gothrough the parents first,” John says, “knowing that he is an adultand if I got an answer I didn’t like, I could always go back and goaround them.” He sent a handwritten letter to the parents. Three dayslater the father called, and then, within minutes, the son was on the phone.The two have met in person several times, but, fittingly, their relationship ismostly online. They are Facebook friends. This, it seems, is the nextunexpected role for Facebook. Jessi is “friends” with Ms. Padula,as well as her biological father, three biological brothers and one sister, hermaternal biological grandmother and aunt. The screen provides connection, butalso distance, a way to tiptoe through what can be the awkward in-betweenterritory of reconnection.

Alexander Dorf’s adoption had been, at first, arelatively open one, and after that first “ask your mother”Facebook contact, Ms. Dorf brought out a safe-deposit box full of oldcorrespondence with Ms. Barber, and went through it all with the teen. Sheshowed him photos of his birth mother and of Alexander’s biologicalfather, James. She told him that communication with the couple had ended afterabout four years, when Ms. Barber offered a second child to the Dorfs butchanged her mind.

After taking all this in, Alexander went back to thecomputer and began an instant message.

“Hi,” he typed.

“Hi. How are you?” she answered.

“I don’t know what to say,” he replied.“I never blamed you or my father. I know you gave me up because you lovedme. My mom always told me that you loved me. I read all the letters and saw allthe pics you sent and I want you to know I am happy.”

She wrote back: “It was the best thing for you. I knowyou had a great life. Better than we could have given you. Your brother andsister are always asking if we can find you.”

That Ms. Dorf did not control the timing of thisconversation is the reality. “If you think that what was private 17 yearsago is still private and that your child needs you to find a birth parent, youare fooling yourself,” she says.

That reality is how Ms. Barber justifies reaching out toAlexander in the first place, even though he was just 16. “Jami had toldme from the beginning that she would tell him the true story,” she says.“I didn’t feel unfair contacting him because I knew he knew.”

Ms. Dorf has since searched for, and found, the birthmothers of her two younger sons. Better to make the first move.

Like John and Mike, most communication between the Dorf boysand their birth families now takes place virtually. Alexander has become closewith his oldest biological brother, and the two play video games together fromseveral states apart, through Wii.

Alexander graduated from high school on Thursday. Ms. Barberwanted to go, but couldn’t take the time off. But she was there inspirit, she says. And there were photos of the ceremony on Facebook.

Lisa Belkin covers family life for The Times and writes theMotherlode blog for nytimes.com.